procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
import os
import stat
import sys
from mercurial.node import hex
from mercurial import (
context,
diffutil,
encoding,
hg,
scmutil,
ui as uimod,
)
print_ = print
def print(*args, **kwargs):
"""print() wrapper that flushes stdout buffers to avoid py3 buffer issues
We could also just write directly to sys.stdout.buffer the way the
ui object will, but this was easier for porting the test.
"""
print_(*args, **kwargs)
sys.stdout.flush()
def printb(data, end=b'\n'):
out = getattr(sys.stdout, 'buffer', sys.stdout)
out.write(data + end)
out.flush()
ui = uimod.ui.load()
repo = hg.repository(ui, b'test1', create=1)
os.chdir('test1')
# create 'foo' with fixed time stamp
f = open('foo', 'wb')
f.write(b'foo\n')
f.close()
os.utime('foo', (1000, 1000))
# add+commit 'foo'
repo[None].add([b'foo'])
repo.commit(text=b'commit1', date=b"0 0")
d = repo[None][b'foo'].date()
if os.name == 'nt':
d = d[:2]
print("workingfilectx.date = (%d, %d)" % d)
# test memctx with non-ASCII commit message
def filectxfn(repo, memctx, path):
return context.memfilectx(repo, memctx, b"foo", b"")
ctx = context.memctx(
repo,
[b'tip', None],
encoding.tolocal(b"Gr\xc3\xbcezi!"),
[b"foo"],
filectxfn,
)
ctx.commit()
for enc in "ASCII", "Latin-1", "UTF-8":
encoding.encoding = enc
printb(b"%-8s: %s" % (enc.encode('ascii'), repo[b"tip"].description()))
# test performing a status
def getfilectx(repo, memctx, f):
fctx = memctx.p1()[f]
data, flags = fctx.data(), fctx.flags()
if f == b'foo':
data += b'bar\n'
return context.memfilectx(
repo, memctx, f, data, b'l' in flags, b'x' in flags
)
ctxa = repo[0]
ctxb = context.memctx(
repo,
[ctxa.node(), None],
b"test diff",
[b"foo"],
getfilectx,
ctxa.user(),
ctxa.date(),
)
print(ctxb.status(ctxa))
# test performing a diff on a memctx
diffopts = diffutil.diffallopts(repo.ui, {b'git': True})
for d in ctxb.diff(ctxa, opts=diffopts):
printb(d, end=b'')
# test safeness and correctness of "ctx.status()"
print('= checking context.status():')
# ancestor "wcctx ~ 2"
actx2 = repo[b'.']
repo.wwrite(b'bar-m', b'bar-m\n', b'')
repo.wwrite(b'bar-r', b'bar-r\n', b'')
repo[None].add([b'bar-m', b'bar-r'])
repo.commit(text=b'add bar-m, bar-r', date=b"0 0")
# ancestor "wcctx ~ 1"
actx1 = repo[b'.']
repo.wwrite(b'bar-m', b'bar-m bar-m\n', b'')
repo.wwrite(b'bar-a', b'bar-a\n', b'')
repo[None].add([b'bar-a'])
repo[None].forget([b'bar-r'])
# status at this point:
# M bar-m
# A bar-a
# R bar-r
# C foo
print('== checking workingctx.status:')
wctx = repo[None]
print('wctx._status=%s' % (str(wctx._status)))
print('=== with "pattern match":')
print(
actx1.status(other=wctx, match=scmutil.matchfiles(repo, [b'bar-m', b'foo']))
)
print('wctx._status=%s' % (str(wctx._status)))
print(
actx2.status(other=wctx, match=scmutil.matchfiles(repo, [b'bar-m', b'foo']))
)
print('wctx._status=%s' % (str(wctx._status)))
print('=== with "always match" and "listclean=True":')
print(actx1.status(other=wctx, listclean=True))
print('wctx._status=%s' % (str(wctx._status)))
print(actx2.status(other=wctx, listclean=True))
print('wctx._status=%s' % (str(wctx._status)))
print("== checking workingcommitctx.status:")
wcctx = context.workingcommitctx(
repo,
scmutil.status([b'bar-m'], [b'bar-a'], [], [], [], [], []),
text=b'',
date=b'0 0',
)
print('wcctx._status=%s' % (str(wcctx._status)))
print('=== with "always match":')
print(actx1.status(other=wcctx))
print('wcctx._status=%s' % (str(wcctx._status)))
print(actx2.status(other=wcctx))
print('wcctx._status=%s' % (str(wcctx._status)))
print('=== with "always match" and "listclean=True":')
print(actx1.status(other=wcctx, listclean=True))
print('wcctx._status=%s' % (str(wcctx._status)))
print(actx2.status(other=wcctx, listclean=True))
print('wcctx._status=%s' % (str(wcctx._status)))
print('=== with "pattern match":')
print(
actx1.status(
other=wcctx, match=scmutil.matchfiles(repo, [b'bar-m', b'foo'])
)
)
print('wcctx._status=%s' % (str(wcctx._status)))
print(
actx2.status(
other=wcctx, match=scmutil.matchfiles(repo, [b'bar-m', b'foo'])
)
)
print('wcctx._status=%s' % (str(wcctx._status)))
print('=== with "pattern match" and "listclean=True":')
print(
actx1.status(
other=wcctx,
match=scmutil.matchfiles(repo, [b'bar-r', b'foo']),
listclean=True,
)
)
print('wcctx._status=%s' % (str(wcctx._status)))
print(
actx2.status(
other=wcctx,
match=scmutil.matchfiles(repo, [b'bar-r', b'foo']),
listclean=True,
)
)
print('wcctx._status=%s' % (str(wcctx._status)))
os.chdir('..')
# test manifestlog being changed
print('== commit with manifestlog invalidated')
repo = hg.repository(ui, b'test2', create=1)
os.chdir('test2')
# make some commits
for i in [b'1', b'2', b'3']:
with open(i, 'wb') as f:
f.write(i)
status = scmutil.status([], [i], [], [], [], [], [])
ctx = context.workingcommitctx(
repo, status, text=i, user=b'test@test.com', date=(0, 0)
)
ctx.p1().manifest() # side effect: cache manifestctx
n = repo.commitctx(ctx)
printb(b'commit %s: %s' % (i, hex(n)))
# touch 00manifest.i mtime so storecache could expire.
# repo.__dict__['manifestlog'] is deleted by transaction releasefn.
st = repo.svfs.stat(b'00manifest.i')
repo.svfs.utime(
b'00manifest.i', (st[stat.ST_MTIME] + 1, st[stat.ST_MTIME] + 1)
)
# read the file just committed
try:
if repo[n][i].data() != i:
print('data mismatch')
except Exception as ex:
print('cannot read data: %r' % ex)
with repo.wlock(), repo.lock(), repo.transaction(b'test'):
with open(b'4', 'wb') as f:
f.write(b'4')
repo.dirstate.set_tracked(b'4')
repo.commit(b'4')
revsbefore = len(repo.changelog)
repo.invalidate(clearfilecache=True)
revsafter = len(repo.changelog)
if revsbefore != revsafter:
print('changeset lost by repo.invalidate()')